A primary goal of a casino is to keep its customers playing as long as possible since longer play generates higher revenues. Casinos are thus interested in maintaining player interest and excitement. When a player's credit balance on a game machine is reduced to zero, the player will often stop playing the game machine. Casinos would prefer that a player not reduce his credit balance to zero and stop gambling. There are several ways in which casinos currently attempt to motivate players to continue gambling, such as by building entertaining games that have large jackpots and favorable payout tables. Another way casinos currently attempt to motivate players to continue gambling is to provide comp points and other benefits to a player for placing bets at a game machine.